Importance of Soil Tests for New Gardens

Even in existing gardens, fertility levels and acidity may changeover several years. It is often worthwhile to repeat testing after four or five years of gardening in an area. With increased fertilizer costs, it is important to get fertility at a desirable level that will not be wasteful or harmful to crops.

Experienced gardeners are often able to guess their yearly fertility needs, but the relatively new gardener will find soil testing well worthwhile. Be prompt in taking a soil test. As the gardening season nears, testing labs become increasingly busy, and it takes longer to process samples. If the sample is taken too late, planting time may pass before results are obtained.

Private labs are good for soil testing. There is a nominal fee charged at Extension centers for soil testing. Soil testing kits are also available for gardeners who want to do their own. These kits may be helpful for the person who has large numbers of samples of test and wants quick results. For the gardener with only a few samples that need testing, the services provided by a professional will be more accurate and economical.

It is important to realize that soil tests give only information about the fertilizer status of the soil, not about other factors that influence plant growth. There is no indication of internal drainage of the soil, nematode infestations, disease or insects present, or other troublesome pests. If a soil test has been taken, and an indication as to the cause of past poor growth is not evident, look to causes other than fertility.

For a soil test to be most useful, the sample should be taken properly. Use a clean pail and spade. Push the spade deeply into the soil, and throw out a spade full of soil. Scrape off the top soil from the back of the hole. Then cut off a slice of soil from the back of the hole with the spade. Try to get this slice 6-7 inches deep and fairly even in thickness. Place this slice in the bucket.

Do this when the soil is not excessively wet. Repeat six or seven times in scattered areas of the garden. Mix these slices thoroughly in the bucket. Remove about a pint of soil and send it or take it to the testing lab. For large areas, or where the soil seems different, or where past plant growth has been variable more than one sample should be taken.

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